The Forbes Sports 50/50 list just came out, and Manchester United was at the top of the list. Real Madrid and Arsenal are also in the top 10. So of course MLS should follow that model right? I mean 2 EPL teams in the top 10 and worth more than a billion dollars seems like the system is working.
Except that EVERY SINGLE NFL team is in the top 50 teams in the world for valuation. Certainly not all of that is due to the parity model. A lot of it has to do with the league wide TV contracts (4 Networks + their own), and some of it has to do with the fact that if you like that style of football there are only 32 pro teams that play it.
The Seattle Seahawks were the last NFL team to break the billion dollar valuation mark. They are nestled in-between Barcelona and Bayern Munich. There are more than a dozen NFL sides worth more than they are. So when a league that was founded by NFL owners (Hunt, Kraft) acts like the NFL realize they do so because they see a league worth tens of billions of dollars under that model.
Here's the list of soccer teams that made the 50
Teams in bold are worth more than a billion dollars. I find it notable that Italy has as many teams in the top 50 as the NBA, Spain as well, though theirs are not in the same valuation range. Germany with one, and England with 4 teams.
As I said before, the NFL has advantages that these leagues do not. Some of them are advantages that MLS has that these other soccer leagues do not. Some of them MLS can never have.
But this is a nice snapshot of WHY MLS does what it does.